1. Field of the Invention
This invention relates to an apparatus for analyzing volatile components from raw or processed food products using either direct gas chromatography or combined direct gas chromatography and mass spectrometry.
2. Description of the Prior Art
In recent years, the analysis of food volatiles by direct gas chromatography (GC) has received much attention as described in the following documents:
Brown, D. F., F. G. Dollear and H. P. Dupuy, JAOCS 49: 81 (1972).
Dupuy, H. P., S. P. Fore, and L. A. Goldblatt, JAOCS 50: 340 (1973).
Fore, S. P., H. P. Dupuy, and J. I. Wadsworth, Peanut Science Vol 3, 86 (1976).
Dupuy, H. P., E. T. Rayner, and J. I. Wadsworth, JAOCS 53: 628 (1976).
Dupuy, H. P., E. T. Rayner, J. I. Wadsworth, and M. G. Legendre, JAOCS 54: 445 (1977).
Jackson, H. W., and D. J. Giacherio, JAOCS 54: 458 (1977).
Williams, J. L., and T. H. Applewhite, JAOCS 54: 461 (1977).
Zlatkis, A., H. A. Lichtenstein, and A. Tishbee, Chromatographia, Vol 6, NO. 2, 67, (1973).
Direct gas chromatographic analysis consists of placing a food sample in a borosilicate glass tubing and introducing this directly into the injection port of a gas chromatograph. Analysis of the number and the magnitude of various volatile materials in the sample is achieved by temperature programming the gas chromatograph, which separates or resolves the volatiles present. This direct (GC) can be further refined to effectively identify such food volatiles by interfacing or "coupling" the gas chromatograph with a mass spectrometer. The latter technique is the most meaningful, since this provides direct information on the actual composition of the food sample. Use of a mass spectrometer, however, requires that essentially all moisture be removed from the volatiles before they are analysed. This has necessitated the minimum use of two-step adsorption-desorption techniques which are critical and time consuming procedures as described in:
Legendre, M. G., H. P. Dupuy, R. L. Ory, and W. O. McIlrath, J. Agri. Food Chem. Vol. 26, No. 5, p 1035-1038 (1978).
Fore, S. P., M. G. Legendre and G. S. Fisher, JAOCS, Vol 55, No. 5, P 482-485 (May 1978)
The procedures outlined in the two above references are not always successful.